Statements of Operations and Accumulated Earnings (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenues	$ 7,597,930	$ 9,469,412	$ 19,941,773	$ 20,934,914
Costs and expenses:
Operating costs	5,944,298	6,900,029	14,347,655	14,561,884
Sales and marketing	657,626	647,400	1,196,050	1,237,913
General and administrative	728,468	735,985	1,616,956	1,086,906
Depreciation	481,367	409,850	949,873	832,223
Total costs and expenses	7,811,759	8,693,264	18,110,534	17,718,926
Net operating (loss) income before other income (expenses)	(213,829)	776,148	1,831,239	3,215,988
Other income (expenses)
Other income	5,906	13,450	13,921	51,603
Interest expense	(80,464)	(58,309)	(159,349)	(116,985)
Total other expenses, net	(74,558)	(44,859)	(145,428)	(65,382)
Net (loss) income	(288,387)	731,289	1,685,811	3,150,606
Accumulated earnings at beginning of period	3,447,778	4,489,796	1,473,580	2,070,479
Accumulated earnings at end of period	$ 3,159,391	$ 5,221,085	$ 3,159,391	$ 5,221,085